The present invention relates to a stretch blow molding machine for producing plastic containers from parisons. More particularly, the present invention relates to a blow mold assembly movably mounted with respect to a blow molding machine to allow for convenient maintenance and servicing.
Blow molding machines for producing plastic containers from heated parisons are widely employed. Conventional blow molding machines commonly include a mechanism for transporting parisons from a heating unit to a blow mold composed of paired halves that can alternately be separated or brought together in sealed engagement. The mold halves include an interior wall configured to the shape of the container to be formed within the blow mold. A parison heated to the appropriate blow molding temperature is transported between the separated paired halves of the mold, which are then brought together to define a mold cavity holding the parison. The parison is then expanded by high pressure gas, with the expanding parison wall eventually contacting walls of the blow mold. The parison is cooled by that contact with the mold wall and is thereby dimensionally stabilized at the desired container configuration. The paired halves of the mold are then separated, and the newly formed container or bottle is ejected or otherwise transported from the mold, ready for further processing. Because this process is highly automated and generally requires only minimal operator supervision, blow molding machines can be compactly built to fit into small building facilities.
However, when maintenance, service, or replacement of the blow mold is required, a compact configuration of a blow molding machine is disadvantageous. For example, replacement of a mold due to wear or to accommodate desired variations in container configuration or size can require extensive disassembly of the blow molding machine to access the blow mold. Such time consuming repairs or modifications can seriously slow factory operations which require a continuous supply of formed containers. What is needed is a blow molding machine which readily provides access to the blow mold and to the auxiliary equipment controlling operation of the blow mold. To speed and simplify maintenance, access to a blow mold assembly should not require any significant disassembly of the blow molding machine.